| 摘要 |
PURPOSE:To obtain the angular information with high accuracy, by extracting out of a demodulating circuit the information about the number of pulses which varies in response to the change of S/N of a received signal which is due to a directional shift of an antenna and counting the result, and using the time changing value with time of the calculated value standardized by the signal time occupying factor as a control signal for tracking the antenna. CONSTITUTION:The reproduced carrier phase, etc. of a demodulating circuit 3 is set by deviating intentionally from the optimum value so that the code error factor P2 of a reproduced data series is made larger than the code error factor P1 of a demodulating circuit 2. When the factor P2 is set 10<2> times as large as the factor P1, the output pulse number of an exclusive OR circuit 4 is approximately proportional to the P2 and therefore to the P1. While the angle shift information on an antenna can be obtained by detecting the time difference of the value obtained by counting the number of pulses at a point A every fixed period since the P1 is a function of the S/N of an input signal. For a signal in intermittent non-signal state in terms of time, the counting for the output pulses of the circuit 4 is discontinued by a standardized counting value generating part 16 for a period no signal exists. |
